Production of flats for carding machines

Abstract

A flat composed of a flat body with a flexible covering fastened thereto and having a plurality of outwardly extending card wires distributed across the covering, for use in carding machines, is produced by disposing such a flexible covering against the outer surface of a cylinder with the outwardly extending wires directed toward the cylinder surface, the outer surface of the cylinder being shaped to define the desired contour of the array of card wire tips; pressing the flexible covering against the outer surface of the cylinder for causing the array of card wire tips to conform to the shape of the outer surface of the cylinder; disposing an associated flat body at a distance from that surface of the covering which is directed away from the cylinder; and filling the region between the flexible covering and the rigid body with a hardenable plastic mass and permitting the mass to harden and to become firmly attached to the flat body and to the covering.

We claim: 
     
       1. A method for producing a flat for use in carding machines, the flat being composed of a rigid support body with a flexible covering fastened thereto, the covering having one side facing the body and the covering further having a plurality of card wires projecting from the covering at a side thereof directed away from the rigid body and distributed across the covering, said method comprising the steps of: disposing a flexible covering, having plural projecting wires, adjacent a convex cylindrical surface with the projecting wires directed toward the surface, the convex surface being shaped to define the desired contour of the card wire tips; pressing the flexible covering toward the cylindrical surface to cause the tip of each of the card wires to touch the cylindrical surface; disposing an associated rigid support body radially spaced from a surface of the covering which is directed away from the cylindrical surface; filling the space between the flexible covering and the rigid body with a hardenable plastic mass, causing said mass to harden and causing said mass to become firmly attached to said rigid body and to said covering, while the flexible covering is being pressed against the cylindrical surface; and then removing the resulting flat from the cylindrical surface. 
     
     
       2. Method as defined in claim 1 wherein said step of pressing is carried out by placing tensioning elements over the surface of the flexible covering which faces away from the cylindrical surface so that the elements extend in the peripheral direction of the cylindrical surface, and fastening ends of said tensioning elements to a portion of the cylindrical surface remote from the surface portion adjacent the flexible covering in a manner to place the elements under tension. 
     
     
       3. Method as defined in claim 2 wherein said step of fastening is carried out by connecting at least one end of each said tensioning element to a tension spring whose free end is pulled over a holding member disposed on the cylindrical surface. 
     
     
       4. Method as defined in claim 2 comprising the final step of cutting off the portions of the tensioning elements which protrude from the flat after the plastic mass has hardened.